The present invention relates to apparatus for pulling cables, such as fiber optic cables, through underground conduit or ductwork. In particular, the invention relates to improvements in a vehicle utilized for such cable pulling operations.
Many utility cables are today disposed in underground ducts. Special systems are utilized for placing cables in the ducts. In recent years, many of the new communication cables are fiber optic cables. Special problems are created in handling fiber optic cable and, therefore, special cable placing systems have been devised for use by utilities companies, such as telephone companies, for placing fiber optic cable in underground ducts.
For this purpose, the utility companies may utilize specially designed trucks which carry the cable placing system to the field location. Typically, access to the underground ductwork is provided by manholes disposed at spaced-apart locations along the duct path. The cable pulling system includes a specially designed winch assembly which takes up a pulling tape which is connected to the leading end of a cable section for pulling it through a length of duct between fiber optic splice locations. The electrical and/or hydraulic power for operating the cable placing system may be carried on board the truck but, at present, there is no convenient way for effecting connections between the winch assembly and the hydraulic and electrical systems.
Furthermore, in prior cable pulling systems, the winch motor and take-up reel are mounted within the truck and, for use, the winch assembly is typically set up for use in the bed of the truck. This limits the accessability of the winch unit to the operator and also limits the access to the manhole. Thus, in order to ensure pulling in the proper direction, it may be necessary to orient the truck in a particular configuration, which may be difficult depending upon the terrain or obstructions in the vicinity of the manhole. Alternatively, the winch assembly must be set up for use on the ground on special support mechanism independent of the truck. This complicates the setup procedure and, depending upon the terrain, may make it very difficult to obtain a stable mount for the winch assembly.